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having only a single river crossing. The Council is exploring the viability of developing a second bridge crossing near the new development. You have been asked to consider the likely distribution of traffic in 10 years time, with and without the second bridge crossing, but assuming that the development goes ahead. Figure 1: Nephest Map showing transport zones Data and Background Information The project manager has assembled some information from the Council and other sources and has also made a number of comments about elements of the analysis. The Council’s Department of Planning and Environment has produced forecasts of the population and employment in each of the Council’s planning zones for the year 2015 (See Table 1). The figures assume that the new industrial development goes ahead and that the residential shift towards the northern suburbs continues. Trends suggest that the average household size will decline to 2.5 by the Year 2015. Table 1: Population and employment forecasts for the year 2015 Your budget does not include funds for a travel survey. However, a recent travel survey has been completed from a nearby town that has similar socio-demographic and transportation system characteristics to Nephest. The travel survey is available to you on Blackboard. Your first task is to develop peak period work trip production and attraction models. The work trip production models should be estimated using the MCA method on the travel survey data according to the classification scheme shown in Table 2. You need to compute the distributions of each group and you can assume these are the same for all zones. You need to comment on how the MCA model compares to the standard cross-classification model. Table 2: Workers/Vehicles Breakdown Workers/Household Vehicles/Household 0 1 2+ 0 1 2+ Information is also available from a nearby town to help you develop a work trip attraction model, shown in Table 3. This model should be developed using linear regression. You should evaluate the model using standard tests for regression models. Table 3: Trip Attraction Data from Nearby Town If the models are satisfactory they are to be used to obtain peak period productions and attractions for each Nephest Zone using the data in Table 1. The forecast attractions should then be factored (balanced to productions) so that the sum of the attractions (across all zones) equals the sum of the forecast productions (across all zones). The trip distribution analysis is to be performed using a production constrained gravity model of the following form: You should continue with row and column balancing, until there is negligible change in the calculated-to-target ratios for both Productions and Attractions. Figure 2 shows the travel times on each link in the network. In this analysis it is to be assumed that the link travel times are constant (i.e. not affected by the volume of traffic). Using this network information you will need to determine two O-D travel time matrices – one for the single bridge case and one for the two bridge case. Note that the intrazonal travel times (i.e., travel times within each zone such as trips from zone 3 to zone 3) can be assumed as 4 minutes. Peak period person trip flows should be converted to vehicle flows on the basis of an assumed average vehicle occupancy of 1.1 persons per car. Required Outputs Your supervisor has asked you to prepare a report, which must include t